So, some 120 UK-based millionaires – including football pundit Gary Lineker, crime writer Val McDermid, screenwriter/director Richard Curtis and at least 100 people you’ve never heard of – have generously written to newbie prime minister Andy Burnham, urging him to tax them more. And they claim to represent 75% of the UK’s millionaires (even though by most estimates there are between two and three million millionaires living in the UK – a lot depends on how you define ‘millionaire’).

Which is nice of them. Even if we can only guess how and why most of these 120 generous souls became a millionaire in the first place. Though, by their own account, not one of them gets up and goes to work for their income every day.

Unfortunately, the ‘Proud to Pay’ millionaires don’t say how – or by how much – Andy Burnham should tax them more. And, as noted previously on this blog, we know that wealth taxes are problematic.

But I have a proposal. I suggest Andy Burnham creates a voluntary wealth tax, for patriotic millionaires and billionaires who believe they should pay more tax. This would avoid the (significant) problems of asset valuation, collection and enforcement associated with most wealth tax proposals. And it would be quick and easy to set up, as the Treasury already has a voluntary donation facility All that Andy Burnham would need to do is establish a system for publishing the amount of extra tax voluntarily donated via that facility by Gary Lineker and each of his fellow ‘Proud to Pay’ millionaires, and then the public could see just how ‘proud to pay’ they really are.

Gary and his mates say they can afford to pay more tax. The mechanism for them to do so already exists (though, strangely, few if any of them are using it). After 14 years of Tory austerity and misrule, our public services really, really need that extra tax. And, as Gary and his mates say they would be ‘proud to pay’ more tax, there really can’t be any objection to us knowing how much more tax they voluntarily pay under my proposal. So, let’s allow the self-declared patriotic “super rich” to put their tax returns where their mouths are.